Hippocalcin in the olfactory epithelium: A mediator of second messenger signaling

Alex Mamman, Jeanette P. Simpson, Alan Nighorn, Yoshikazu Imanishi, Krzysztof Palczewski, Gabriele V. Ronnett, Cheil Moon

Research output: Contribution to journalArticle


Intracellular Ca 2+ plays an important role in a variety of second messenger cascades. The function of Ca 2+ is mediated, in part, by Ca 2+-binding proteins such as calmodulin, calretinin, calbindin, neurocalcin, recoverin, and visinin-like proteins (VILIPs). These proteins are highly expressed in rat olfactory receptor neurons (ORNs) and are localized to distinct intracellular regions. In the present study, we have identified another Ca 2+-binding protein, hippocalcin, in the rat olfactory epithelium (OE). Olfactory/brain hippocalcin shows high sequence homology with hippocalcins expressed in mice and humans. Hippocalcin was predominantly localized to the olfactory cilia, the site of the initial events of olfactory signal transduction, and was found to regulate the activity of ciliary adenylate cyclases (ACs) and particulate guanylyl cyclases (GCs) in a Ca 2+-dependent manner. These data indicate that hippocalcin is expressed in rat ORNs, and is likely to regulate second messenger cascades in a Ca 2+-dependent manner.

Original languageEnglish (US)
Pages (from-to)1131-1139
Number of pages9
JournalBiochemical and Biophysical Research Communications
Issue number4
StatePublished - Oct 1 2004


ASJC Scopus subject areas

  • Biochemistry
  • Biophysics
  • Molecular Biology

Cite this

Mamman, A., Simpson, J. P., Nighorn, A., Imanishi, Y., Palczewski, K., Ronnett, G. V., & Moon, C. (2004). Hippocalcin in the olfactory epithelium: A mediator of second messenger signaling. Biochemical and Biophysical Research Communications, 322(4), 1131-1139. https://doi.org/10.1016/j.bbrc.2004.07.123